PAN Ke-Jia~(1,2),WANG Wen-Juan~3,TAN Yong-Ji~2,CAO Jim-Xing~31 School of Mathematical Sciences and Computing Technology,Central South University,Changsha 410075,China2 School of Mathematical Sciences,Fudan University,Shanghai 200433,China3 State Key Lab of Oil and Gas Reservoir Geology and Exploitation.Key Lab of Earth Exploration and In formation Techniques of Ministry of Education,Chengdu University of Technology,Chengdu 610059,China